Randy L Rasmussen/The OregonianBrian Stamps was stranded at second base in the bottom of the ninth, stopping the Beavers' rally and hopes for a comeback win.

CORVALLIS -- If there is a silver lining from Oregon State’s 4-3 loss to USC Sunday at Goss Stadium -- the first Pacific-10 series loss for the No. 2 Beavers -- it is this: Arizona State dropped its series finale to Washington, which means OSU is still alone in first place.

But that doesn’t lessen the sting of Sunday’s game for Oregon State coach Pat Casey and his players.

“You always go through ups and downs,” Casey said. “We got swept at home in 2007 by Arizona State with two weeks left and we won a national championship, but you certainly don’t want (to lose). We’ve been playing much better baseball than we’ve played the last couple days. We didn’t play well at Washington (last week) on the last day either, so it’s disappointing.”

USC scored three of its four runs with two outs, recording six hits off OSU starter Josh Osich. The junior left-hander, usually the Saturday starter, said he was told Saturday morning that freshman Ben Wetzler would throw a day early. Osich said he did not ask for an extra day’s rest, but that it shouldn’t matter.

“It didn’t change anything,” Osich said. “We just didn’t come out and play like we should have.”

Asked about the Beavers’ struggle to record a third out in multiple innings, Osich just shrugged.

“They’re a good hitting team, so you can’t really relax,” said Osich, who took his third loss of the season. “As a team we just didn’t go out there and play good. We had good stints here and bad stints there; that’s just baseball.”

Oregon State left 10 runners on base, including three in a crucial fifth inning with USC leading 2-1. Michael Miller reached first on a single before Brian Stamps and Andrew Susac were walked to load the bases, but Jared Norris struck out looking to end the inning.

“For these guys to battle, and for (starter Logan) Odom to battle, it was unbelievable,” said USC coach Frank Cruz. “To beat a pitcher like Osich is a huge -- he’s going to be a first rounder. My hat’s off to OSU -- they’re going to go a long way in the playoffs, and I hope they do.”

Odom, who played high school ball at North Medford, picked up his fifth win of the season.

Stamps, the Beavers’ center fielder, reached base four times but scored only once. A sacrifice fly from designated hitter Kavin Keyes in the ninth scored Miller to bring Oregon State within a run and moved Stamps into scoring position with two outs. It looked like Beavers, who have made comebacks all season, might be on the verge of another, but Andrew Susac grounded out to end the game.

Despite the loss, OSU is still in control of its future. A series win next weekend at Oregon would give the Beavers at least a share of the conference title. Arizona State and UCLA, who are both a game behind the Beavers at 16-8, play each other in Tempe. Should OSU wind up tied for the Pac-10 championship the Beavers would get the automatic NCAA bid because they own series wins over both teams. OSU is expected to host a regional when the postseason starts June 3, but the Beavers’ hope at being a national seed took a hit with the series loss to USC.

But all Casey can think about right now is next weekend, when Oregon State travels to Eugene.

“It won’t be very good for us if we play (Oregon) the way we played this weekend,” Casey said, adding that he’s concerned OSU isn’t “playing the game right.”

“We’re not doing the things in baseball that you’re supposed to do -- catch balls, hit with men in scoring position, throw strikes, get ahead of hitters, all the little things. Today, those things cost us.”